STRSV/DTRSV/CTRSV/ZTRSV

Solve triangular system

Example 1 Perform REAL*4 forward elimination using the 75-by-75 unit-diagonal lower-triangular real matrix stored in an array A whose dimensions are 100-by-100, and x is a real vector 75 elements long stored in an array X of dimension 100.

CHARACTER*1 UPLO,TRANS,DIAG

INTEGER*4 N,LDA,INCX

REAL*4 A(100,100),X(100)

UPLO = ’L’

TRANS = ’N’

DIAG = ’U’

N = 75

LDA = 100

INCX = 1

CALL STRSV (UPLO,TRANS,DIAG,N,A,LDA,X,INCX)

Example 2 Perform REAL*4 back substitution using the 75-by-75 nonunit-diagonal, upper-triangular real matrix stored in an array A whose dimensions are 100-by-100, and x is a real vector 75 elements long stored in an array X of dimension 100.

INTEGER*4

N,LDA

REAL*4

A(100,100),X(100)

N =

75

 

LDA

= 100

 

CALL STRSV (’UPPER’,’NONTRANS’,’NONUNIT’,N,A,LDA,X,1)

336HP MLIB User’s Guide